Conventionally, liquid crystal display devices are used as a display device for small-sized, thin devices, such as notebook computers, portable telephone devices, and portable TVs. Liquid crystal display devices are also increasingly used as a display device in vehicle instruments for displaying vehicle information and traffic information. The liquid crystal display devices are provided with a lighting unit for illuminating a liquid crystal panel. The lighting unit typically includes a light source, and a light guide plate which converts a light bundle from the light source into a planar light bundle optimized for illuminating the liquid crystal panel. An example of this type of lighting unit is disclosed in Patent Document 1 indicated below. Patent Document 1 discloses a lighting unit provided with a light source and a light guide member. Light emitted from the light source enters a light entry portion of the light guide member and exits from a light exit portion of the light guide member to illuminate a liquid crystal panel which is the member to be illuminated. The light guide member has a substantially circular shape, and is provided with light sources. The light sources are disposed on a peripheral edge of the light guide member such that the directions of light emitted from the light sources can all intersect each other.